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son (of others); boy; young master
green young man from a well-to-do family; young man innocent of the ways of the world
お坊っちゃんはどこにいますか。
Where is the young master?
お坊っちゃんだと思われた。
I was thought to be a sheltered rich kid.
お坊っちゃん育ちで世間知らずだ。
He's naive because he was raised pampered.